might have done sth. 总是表示“本可做某事，而实际并没有做”的意思吗？
除用于虚拟语气之外,might have done 一般还可以表示三种意思：
A. 本可以做某事，而实际上并没有做，有时含有抱怨的口吻。
例句见上条。
B. 推测过去实际上存在的可能性。例句见上条。再如：
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One reason that we have not had his letter yet is that he might have sent it to our old address by mistake. 我们尚没有收到他的信的原因是,他可能错误地把信寄到我们旧地址那里去了。
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I might have come to a wrong conclusion. (Priestley) 我可能得出了错误的结论。
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That was a bad place to go skiing. You might have broken your leg. (BEU) 到那个地方去滑雪很危险。你可能会把腿摔断的。
C. 仿佛是,好像是。
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How quickly time passed! It might have happened yesterday. (Mansfield) 时间过得真快！这件事就好像是昨天发生似的。
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A taxi cab, which might have been used by Lot and his family as they left Sodom and Gomorrah, took my luggage and struggled bravely through the traffic. 一辆出租马车，好像当年罗特和他全家离开索多姆和高莫拉城时乘坐过的那辆，载着我的行李，费力而又惊险地穿行在熙熙攘攘的车流中。
还应补充的是,might have + guessed (known, suspected), 用来加强抱怨的意味:
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I might have guessed he'd fail to read the instructions. (LEG) 我早知道他是不会看说明书的。
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I might have known someone would upset her. 我早知道有人会折磨她的。请做下面的英语试题：
Our friends' plane landed but they weren't on it. They ____ the plane. A. can have missed B. may have missed C. can have lost D. may have lost(Nelson, 300C)